Examining the Relationship Between Social Motivation and Internalizing Symptoms in Autistic People: A Systematic Review and Meta-Analysis.

The social motivation theory hypothesizes that autistic individuals' experience diminished social motivation due to reduced social reward, social orienting, and social maintaining. Low social motivation has been linked to increased vulnerability to internalizing difficulties within this population. This systematic review and meta-analysis examined the relationship between social motivation and internalizing symptoms across the lifespan in autistic individuals. Relevant research papers until February 2025 were identified by searching EMBASE, PsycINFO, PubMed, and Web of Science databases (PROSPERO protocol: CRD42024547863). The systematic review included 14 studies (n = 4590). A total of three meta-analyses were run using Pearson's correlation coefficients between social motivation and (1) anxiety, (2) depression, and (3) social anxiety, and the moderating effect of age, sex, and study quality were assessed using meta-regressions. Sensitivity analyses were run to assess whether one study was influencing the results of the meta-analysis. Greater difficulties with social motivation are associated with increased anxiety, depression, and social anxiety, with a moderate pooled effect size across all domains. Sensitivity analyses did not significantly alter any of the results. Age, sex, and quality of study were nonsignificant moderators. Reduced social motivation may be associated with an increased vulnerability to internalizing difficulties in autistic individuals. The stability across age, sex, and study quality highlights social motivation as a potential transdiagnostic target for intervention in autistic individuals.